Anybody can write code that a computer can understand. Good programmers write code that humans can understand.
Clean code refers to code that is simple to read, understand, and maintain. This term was coined by Robert Martin, also known as Uncle Bob.
Code is read more often than written.
This is why we want to keep our code as readable as possible, especially when working in a team.
Below you will find an example for a small script that we want to discuss. We want to take a closer look and ask ourselves how it can be improved. The idea behind this script is to make a request to a server, fetch a list of customers and filter for specific users (in this case users from Spain that are of a minimum certain age). After that we send the data to a server.
In part one of our series we discussed a small (Python) script. We went through the most obvious code smells and fixed them in the code below.
http_user_service_url = "https://api.coding-on-my-mind.com/users"
http_user_service_username = os.envviron.get("HTTP_USER_SERVICE_USERNAME")
http_user_service_password = os.envviron.get("HTTP_USER_SERVICE_PASSWORD")
age_in_years = 18
userdata_filename = "./clients.csv"
from datetime import datetime, timedelta
import sys
import requests
from requests.auth import HTTPBasicAuth
from configuration import http_user_service_url, http_user_service_username, http_user_service_password,
userdata_filename, age_in_years
import csv
f = open(userdata_filename, 'w')
writer = csv.writer(f)
now = datetime.now()
min_age = now - timedelta(days=age_in_years * 365)
response = requests.get(http_user_service_url, auth=HTTPBasicAuth('u938453', 'Wxc6$78gfsgOi8kr'))
# print(response)
if response.status_code != 200:
print(f"Could not make a successful request to ${url}")
sys.exit(1)
response_dict = response.json()
all_users = response_dict['results']
counter = 0
for user in all_users:
birth_date_str = user['birth_date']
birth_date = datetime.fromisoformat(birth_date_str)
if birth_date < min_age:
if user['country'] == "Spain":
new_user = {
"name": f"{user["title"]} {user["first_name"]} {user["last_name"]}",
"street": user["street"],
"city": f"{user["postal_code"]} {user["city"]}",
"country": user["country"],
}
if counter == 0:
writer.writerow(new_user.keys())
writer.writerow(new_user.values())
counter = counter + 1
else:
print(f"User with id ${user['id']} is not from Spain")
else:
print(f"User with id ${user['id']} is not old enough and will be skipped")
f.close()
We improved the code a little bit in comparison to the code from our first part.